The Kittila mine is located in the Lapland region of northern Finland, approximately 900 km north of Helsinki and 150 km north of the Arctic Circle. The climate is moderated by the Gulf Stream off the coast of Norway, such that northern Finland’s climate is comparable to that of eastern Canada and mining work can be carried out year-round. With a mine life estimated through 2034, Kittila is our longest-life mine; its proven and probable mineral reserves contain 4.1 million ounces of gold (30 million tonnes grading 4.16 g/t gold) as of December 31, 2020.
The Kittila property covers 192 square km, stretching 25 km along the Suurikuusikko Trend, a major gold-bearing shear zone. The mine area includes a group of six gold deposits along a 4.5-km segment of the trend. The largest of the deposits is the Main Zone in the Suuri, Roura and Rimpi areas that contain most of the current mineral reserves and mineral resources at Kittila. The other deposits are the undeveloped Sisar Zone, which is sub-parallel to the Main Zone, as well the Etela and Ketola zones.
As part of a major expansion project at Kittila, the commissioning of the expanded mill with its 25% increase in capacity was completed ahead of schedule in 2020 and the ramp-up towards the design capacity of 2.0 million tonnes per year is ongoing.
The sinking of a 1,044-metre deep shaft as part of the expansion project experienced delays due to COVID-19 travel restrictions, and commissioning is now expected to be completed during the first half of 2022.
The expansion project is expected to increase the efficiency of the mine and decrease or maintain current operating costs while providing access to the deeper mining horizons. This increased mining rate will be supported by the development of the Sisar Zone and deeper portions of the Main Zone.
Geology
The region around the Kittila mine is underlain by mafic volcanic and sedimentary rocks of the Kittila Greenstone Belt that trend north to north-northeast and are nearly vertical. This greenstone belt is similar to those hosting our Canadian deposits in Quebec’s Abitibi region and Nunavut. The contact between iron-rich and magnesium-rich volcanic and sedimentary rocks consists of a transitional zone (the “Porkonen Formation”) varying between 50 and 200 m in thickness. This zone is strongly sheared, brecciated and characterized by intense hydrothermal alteration and gold mineralization, features consistent with major brittle ductile deformation zones. The zone is part of a major north-northeast-oriented shear zone (the “Suurikuusikko Trend”). The Porkonen Formation hosts the Kittila gold deposit, which contains multiple mineralized zones stretching over a strike length of more than 25 km.
Mineralization
Work has focused on a 4.5-km segment of the Suurikuusikko Trend that hosts the six main zones of known gold mineral reserves and mineral resources – Ketola, Etela, Suuri, Roura, Rimpi and Sisar. The Sisar Zone is located to the east of the main Kittila ore zone, and in proximity to existing underground infrastructure. Gold mineralization in these zones is associated with intense hydrothermal alteration (carbonate-albite-sulphide), and is almost exclusively refractory, locked inside the fine-grained sulphide minerals arsenopyrite and pyrite. The remainder is free gold, which is manifested as extremely small grains of gold in pyrite.
Mining
The underground method is open stoping followed by delayed backfill. Approximately 16 km of tunnels are developed each year to ensure sufficient ore production is available to keep the mill supplied. After extraction, stopes are filled with cemented backfill or paste backfill to allow the safe mining of adjacent stopes. Ore is trucked to the surface crusher using underground haul trucks via the 4,400-metre-long ramp access system. Once commissioned, the new 1,044-metre-deep shaft will have hoisting capacity of 2.7 million tonnes per year (2.0 million tonnes of ore and 0.7 million tonnes of waste). In addition, the shaft is expected to provide access to the mineral resource areas below 1,150 m depth, where ongoing exploration programs show promising results.
Processing
At Kittila’s processing plant, ore is treated by grinding, flotation, pressure oxidation, and carbon-in-leach circuits. Kittila has Agnico Eagle’s only pressure oxidation circuit (autoclave), which is required because of the ore’s refractory nature. Gold from the leach circuit is recovered from the carbon in a Zadra elution circuit and recovered from solution using electrowinning, and then smelted in an electric induction furnace and poured into doré bars. Gold recovery of 86% is expected over the life of the mine. Ore is processed in a surface processing plant with a current capacity of 6,000 tonnes per day. The mill expansion involved installation of a secondary crushing circuit, new thickener and reactor capacity, and minor modifications to the existing grinding circuit and autoclave.
In 2020, the Company was granted the permits to expand mine production to 2.0 Mta and the use of a new discharge location. The new discharge waterline construction was completed and commissioned at the end of 2020. Engineering design of a water treatment plant to manage total nitrogen concentration and loading is underway and construction is planned for 2022 with commissioning expected in early 2023.
Exploration
Exploration at the Kittila mine is focused on extending the Main and Sisar zones northward, southward and at depth in the Roura and Rimpi areas to increase the mineral reserves in the large orebody. Sisar is subparallel to and 50 to 300 m east of the main Kittila mineralization and remains open at depth and along strike.
During 2021, a substantially increased program of 65,000 metres of drilling is planned to further explore the Kittila mine’s mineral reserve and mineral resource potential and to evaluate the potential to develop the Sisar Zone as a new mining horizon. Another 9,500 metres of exploration drilling will target mineralization beyond the current mineral resource area, especially at depth. Outside of the mining licence areas, 15,000 metres of diamond drilling is planned for exploration along the Suurikuusikko, Kapsa and Hanhimaa trends.